An Egyptian holds up posters during a protests against President Mohamed Morsi and the Muslim Brotherhood as they join thousands at Egypt's landmark Tahrir square on June 30, 2013 in Cairo.

Egypt braced for mass rallies with President Mohamed Morsi's opponents determined to oust him and his Islamist supporters vowing to defend his legitimacy to the end, stoking fears of a violent first anniversary of his taking office.

An Egyptian protesters chant slogans and hold anti-Egypt's Islamist President Mohammed Morsi poster with Arabic reads, "Rebel and down with Muslim Brotherhood rule," during a rally in Tahrir Square, the focal point of Egyptian uprising, in Cairo Sunday, June 30, 2013.

Organizers of a mass protest against Egyptian President Mohammed Morsi claimed Saturday that more than 22 million people have signed their petition demanding the Islamist leader step down, asserting that the tally was a reflection of how much the public has turned against his rule. Arabic reads, "Leave."

Egyptians and their security forces prepared for demonstrations on Sunday that may determine their future, two years after people power toppled a dictator and ushered in a democracy crippled by bitter divisions.

In 2011, when hundreds of thousands of people took to the streets to end Mubarak's authoritarian three-decade rule, they held up posters of regime figures with their faces crossed out.

This time, protesters are holding pictures of senior leaders of the Muslim Brotherhood, from which Morsi hails.

Morsi was elected a year ago in Egypt's first ever free vote. But today, his critics accuse him of betraying the revolution by concentrating power in the hands of Islamist groups.

They accuse him of breaking his promise to be a president "for all Egyptians" and letting the economy dive into free fall.

Thousands of Egyptians demanding the ouster of Morsi are gathering at Cairo's central Tahrir Square and the presidential palace at the start of a day of massive, nationwide protests many fear could turn deadly. The poster with Arabic at left, reads, lLeave, huge year strike, 6/30."